Shelf unit



FIG. 1 is a front and left side perspective view of a shelf unit showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a left side elevational view, the right side being a mirror image thereof;

FIG. 4 is a front elevational view of a second embodiment of the shelf unit shown in FIG. 1; and

FIG. 5 is a top plan view thereof.

The pattern schematically depicted on the shelves and back walls in FIGS. 1, 2, and 3 is continuous throughout. 

The ornamental design for a shelf unit, as shown and described. 